global magnetic connectivity in the hollween events of 2003 (zhang et al. 2007; zhou et al. 2006)

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Global magnetic connectivity in the Hollween events of 2003 (Zhang et al. 2007; Zhou et al. 2006). A current sheet traced from the sun to the interplanetary space. G. P. Zhou, C. J. Xiao, J. X. Wang, M. S. Wheatland, and H. Zhao. - PowerPoint PPT Presentation

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Global magnetic connectivity in the Hollween events of 2003 (Zhang et al. 2007; Zhou et al.

2006)

A current sheet traced from the sun to the interplanetary space

G. P. Zhou, C. J. Xiao, J. X. Wang, M. S. Wheatland, and H. Zhao

Key Laboratory of Solar Activity, National Astronomical Observatories, Chinese Academy

of Sciences, Beijing 100012, China

CME initiation models:

1, classical "CSHKP" reconnection model (Carmichael 1964; Sturrock 1966; Hirayama 1974; Kopp & Pneuman 1976), which were advanced by many later studies (see, e.g., Heyvaerts, Priest, & Rust 1977; Sturrock et al. 1984; Shibata et al. 1995; Tsuneta 1997; Shibata 1999; Chen & Shibata 2000; Lin & Forbes 2000; Moore et al. 2001):

2 magnetic breakout model (Antiochos, Devore, &

Klimchuk 1999) or shearing arcade models (Mikic

1994), external magnetic reconnection to occur on the top of the sheared arcade.

3 Double-current-sheets reconnection model of CMEs: reproduce the behavior of both magnetic breakout and standard flare models (Zhang et al. 2005, 2006, 2007)

5

In the actual observations, a CS is supposed to be thin enough to make its direct detection quite difficult during a CME event.

CS reports in post-CMEs: • emission from unusually high temperature ions in UVCS data (Kohl et al. 1995; Raymond et al. 2003). • raylike bright structures in LASCO and SMM (e.g., Ciaravella et al. 2002; Ko et al. 2003; Raymond et al. 2003, Webb et al. 2003, Lin et al. 2007).

No CS observation is reported in pre-CME

Dec. 13 2006 The powerful solar eruptive event manifests itself in AR 10930; X 3.4 Flare; fast halo CME; Magnetic cloud; DST = -187 nT (Zhang, Li, & Song 2007; Imada et al. 2008; Kubo et al. 2007; Isobe et al. 2007; Guo & Ding 2008; Jing et al. 2008a; Jing, Chae, & Wang 2008b; Yan, Huang, & Chen 2007; Ning 2008; Liu et al. 2008, and so on)

two kinds of blue shifted phenomenon accompanying with the X3.4 flare in soft X-rays (Asai et al. 2008).

X-ray observations

before flare after flare

Two kinds of strong blue shift (Asai et al. 2008).

faint arc-shaped ejection

plasmoid ejection

Nonlinear forcefree extrapolation(Wheatland, 2007)

after flarebefore flare

current sheet-like structure in LASCO observations

separation of STEREO A and B is ≈7500 km

Identifying interplanetary current sheet (ICS):

“1”– sheath“2”– interplanetary arcades“3”– ICS“4”-- MC

Density ~10-8 A m-2

T~1.5x105k

thickness ~5 x105kmV ~ 841 km s-1

interval ~10 min

Solar source Interplanetary structure

Conclusions:

A large-scale transverse CS is identified before flare/CME , play key important role in CME initiation, and extend from the Sun to the interplanetary space.

As a supplement for standard flare model, provide new understanding for CME eruption and propagation.

A&A 525, A156 (2011)

Parameters of Current Sheet

• Current density: Jz,max~10-8 A/m2

• V ~ 841 km s-1 interval ~10 min , T~1.5x105k

• Thickness: ~10min*841 km/s=5x105km

Kataoka R, Jet al., JGR,2009

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